Duh, I'm an idiot, I only tested policy.HTTP and *NOT* supplying a policy (which I believed was equivalent to using policy.default).

policy.default and policy.SMTP do indeed produce a newline-less subject indeed.

I only tested policy.HTTP because the docs talk about unlimited line-length, but that's a problem of the docs, but rather, a problem of my idiocy.

Given this, I agree with everything you said. Personally I'd prefer if policy.default was the default, but I guess that won't change due to backwards compatibility reasons and I guess it'd be excessive to create a new set of function calls and deprecate the old, so I'm happy if this remains closed.

Apologies for my stupidity,

Álex